Dental wedge

ABSTRACT

A dental wedge for use in the inter-proximal space between adjacent teeth is described. The wedge comprises a taper section ending at a tip, and a body section extending to the tapering section at one end. The body section has an inverted V-shaped cross-section, flexing of the sides of the V-shape allows the wedge to adapt to various contours of the inter-proximal space. The mid-portion of the body section is narrower than at least a portion of the wedge either end of the mid-portion.

FIELD OF THE INVENTION

The present invention relates to an apparatus for use with dentalmatrixes in the placement of dental fillings.

SUMMARY OF THE PRIOR ART

To enable the dental professional to place composite fillings, matrixesare used. A matrix is a device which wraps around the tooth and acts asa mould to contain composite resins before they are cured. Matrices aregenerally formed of plastic or stainless steel and are eithercircumferential or sectional. Sectional matrices fit only in oneproximal area of the tooth while circumferential matrix bands fit aroundthe entire circumference of the tooth. Matrixes are secured in place bythe use of wedges and/or clamps. The prior art wedges are generally madeof wood or plastic and are placed between the matrix and an adjacenttooth. Wedges are used to hold the matrix against the tooth being filledand to temporarily separate the tooth being filled and the adjacenttooth. In the prior art wedges are not flexible or appropriately shapedand often cause punctures to the soft tissues and so are traumatic.Local anesthetics are often required.

As used herein the term “and/or” means “and” or “or”, or both.

As used herein “(s)” following a noun means the plural and/or singularforms of the noun.

The term “comprising” as used in this specification and claims means“consisting at least in part of”. When interpreting statements in thisspecification and claims which include that term, the features, prefacedby that term in each statement, all need to be present but otherfeatures can also be present. Related terms such as “comprise” and“comprised” are to be interpreted in the same manner.

It is intended that reference to a range of numbers disclosed herein(for example, 1 to 10) also incorporates reference to all rationalnumbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5,7, 8, 9 and 10) and also any range of rational numbers within that range(for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7).

The entire disclosures of all applications, patents and publications,cited above and below, if any, are hereby incorporated by reference.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a wedgefor securing dental matrices which is an improvement on the prior artsystems and devices or which will at least provide the industry with auseful choice.

The present invention may be said to consist in a dental wedge, for usein the inter-proximal space between adjacent teeth, comprising

a taper section ending at a tip,

a body section extending to said tapering section at one end,

wherein said body section has an inverted V-shaped cross-section,flexing of the sides of the V-shape allowing the wedge to adapt tovarious contours of the inter-proximal space, and

a mid-portion of said body section is narrower than at least a portionof the wedge either end of said mid-portion.

Preferably said body section, as viewed from said side is ofsubstantially uniform depth.

Preferably said wedge includes a handle and said body section extendsbetween said handle at one end and said tapered section at the otherend.

Preferably said body section, viewed from a side, has a curved profile,rising to the handle and taper section, and curved downward toward saidmid-portion.

Preferably handle comprises a flat member with a hole therethrough

Preferably the V-shaped cross-section is continuous along the length ofsaid body section and taper section.

Preferably the contour of said wedge transitions smoothly along thelength of the wedge.

Preferably said tip is blunt, with a leading end radius greater than 0.2mm, and being at least 1.3 min wide 3 mm from said tip.

Preferably the side faces of said V-shaped cross-section are concave.

Preferably said sides can flex elastically toward each other duringinsertion through a space narrower than the widest width of said wedge.

Preferably the length of said wedge, excluding the handle, is between 10mm and 20 mm.

Preferably the maximum width of said wedge, excluding said handle, isbetween 0.8 mm and 3.6 mm.

Preferably the height of a cross-section of said wedge in said bodysection is between 1.2 mm and 2.4 mm.

Preferably at its lowest point along the wedge, the upper edge of thewedge (excluding any handle) is spaced between 0.6 mm and 1.1 mm from aline extending between the upper edge of the wedge adjacent the tip andthe upper edge of the wedge adjacent the handle.

Preferably said V-shaped cross-section includes an angle of between 50°and 25° at the most open cross-section.

Preferably said V-shaped cross-section at said mid-portion includes anangle of between 35° and 15°.

In a second embodiment the present invention may be said to consist in adental wedge, for use in the inter-proximal space between adjacentteeth, comprising

a taper section ending at a tip,

a body section extending to said tapering section at one end,

wherein said body section has an inverted V-shaped cross-section,flexing of the sides of the V-shape allowing the wedge to adapt tovarious contours of the inter-proximal space, and

said body section, when viewed from a side, has a curved profile, risingto said taper section and the end opposite said tapered section, andcurved downward toward a mid-portion.

Preferably said wedge includes a handle and said body section extendsbetween said handle at one end and said tapered section at the otherend.

In a third embodiment the present invention may be said to consist in adental wedge, for use in the inter-proximal space between adjacentteeth, comprising

a taper section ending at a tip,

a body section extending to said tapering section at one end,

wherein said body section and said tapered section comprise a pair ofsidewalls converging to form an upwardly facing ridge, flexing of thesidewalls allowing the wedge to adapt to various contours of theinter-proximal space, and

said body section, when viewed from a side, has a curved profile, risingto said taper section and the end opposite said tapered section, andcurved downward toward a mid-portion.

Preferably said body section is of substantially consistent height alongsaid body section.

Preferably said sidewalls are steeper at said mid-portion than atregions toward either end of said wedge.

In a third embodiment the present invention may be said to consist adental repair site comprising a pair of adjacent teeth, aninter-proximal space between said teeth, a cavity, prepared for filling,facing said inter-proximal space, a dental matrix in said inter-proximalspace, dividing said teeth and forming a mold for a filling of saidcavity, and a wedge as claimed in any one of claims 1 to 21 including ahandle passing through said inter-proximal space adjacent the gingivaltissue, with said handle protruding at one side with said tip protrudingat the other side and said handle and tip rising away from said gingivaltissue, and a side of the body section pressing against a lower portionof said dental matrix.

In this specification, where reference has been made to external sourcesof information, including patent specifications and other documents,this is generally for the purpose of providing a context for discussingthe features of the present invention. Unless stated otherwise,reference to such sources of information is not to be construed, in anyjurisdiction, as an admission that such sources of information are priorart or form part of the common general knowledge in the art.

This invention may also be said broadly to consist in the parts,elements and features referred to or indicated in the specification ofthe application, individually or collectively, and any or allcombinations of any two or more of said parts, elements or features, andwhere specific integers are mentioned herein which have knownequivalents in the art to which this invention relates, such knownequivalents are deemed to be incorporated herein as if individually setforth.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred forms of the present invention will now be described withreference to the accompanying drawings in which;

FIG. 1 is a plan view of the dental wedge of the present invention,

FIG. 2 is a side view of the dental wedge of the present invention,

FIG. 3 is a bottom view of the dental wedge of the present invention,

FIG. 4 is an end view of the dental wedge of the present invention,

FIG. 5 is an orthogonal view from the side of the dental wedge of thepresent invention,

FIG. 6 is an orthogonal view from the bottom of the dental wedge of thepresent invention,

FIG. 7 is a plan view of an alternate embodiment of the dental wedge ofthe present invention,

FIG. 8 is an end view of the dental wedge of FIG. 7,

FIG. 9 is an orthogonal view from the top of the dental wedge of FIG. 7,

FIG. 10 is an orthogonal view from the bottom of the dental wedge ofFIG. 7,

FIG. 11 is a view of dental wedge of the present invention in use,illustrated with a partial cross section of a tooth,

FIG. 12 is a side view of the dental wedge of the present invention inuse,

FIG. 13 is a plan view of an alternate embodiment of the dental wedge ofthe present invention,

FIG. 14 is a partial cross section side view of the dental wedge of FIG.13,

FIG. 15 is a cross section along the line B-B of the dental wedge ofFIG. 13,

FIG. 16 is a cross section along the line C-C of the dental wedge ofFIG. 13,

FIG. 17 is a cross section along the line D-D of the dental wedge ofFIG. 13,

FIG. 18 is a plan view of a further alternate embodiment of the dentalwedge of the present invention,

FIG. 19 is a partial cross section side view of the dental wedge of FIG.18,

FIG. 20 is a cross section along the line B-B of the dental wedge ofFIG. 18,

FIG. 21 is a cross section along the line C-C of the dental wedge ofFIG. 18,

FIG. 22 is a cross section along the line D-D of the dental wedge ofFIG. 18,

FIG. 23 is a plan view of a further alternate embodiment of the dentalwedge of the present invention,

FIG. 24 is a partial cross section side view of the dental wedge of FIG.23,

FIG. 25 is a cross section along the line B-B of the dental wedge ofFIG. 23,

FIG. 26 is a cross section along the line C-C of the dental wedge ofFIG. 23, and

FIG. 27 is a cross section along the line D-D of the dental wedge ofFIG. 23.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

Referring to FIG. 1 the wedge comprises a one piece member of semi-hardor hard plastic or thermoplastic and has three main parts, a bodysection 1, a tapered end section 8 and a handle section 2. The wedge hasa ridge 10 and two sides 16 and 16′ converging towards the ridge. Theridge 10 runs along the top of the body section 1 and tapered end 8.

Referring to FIG. 2 the body section 1 when viewed from the side has acurved profile. The ridge 10 of the body section 1 rises from the centre12 of the body section 1 to the handle end 11 of the body section 1 andat the opposite end to the tapered end section 8

The tip 5 of the tapered end section 8 is blunt to help prevent damagewhen the wedge is inserted between teeth. The leading end radius 18 ofthe tip 5 of the tapered end 8 is greater than 0.2 mm, with the wedgetapering out, so that it is at least 1.3 mm wide 3 mm from the tip 5.

The wedge between the tip 5 and adjacent the handle 11 is between 10 mmand 20 mm long. At the lowest point along the ridge 10, the upper edgeor ridge 10 of the wedge (excluding any handle) is spaced 19 between 0.6mm and 1.8 mm from a line 18 extending between the upper edge or ridge10 of the wedge adjacent the tip 5 and the upper edge of the wedgeadjacent the handle 11.

Referring to FIG. 3 the when viewed from the underside the wedge has ahollow 6. The wedge body 1 in cross section as seen in FIG. 4 is aninverted V shape. The sides of the wedge body 16 rise to the ridge 10.The angle 15 of the V-shaped cross section is between 25 degrees and 50degrees at the most open cross-section. The V shaped cross section mayextend to the tapered end section 8. The sides 16 of the wedge aresufficiently flexible to flex together as the wedge is inserted into theinter-proximal space. The side faces of the sides 16 are optionalconcave.

The optional handle 2 is flat member and optionally has a hole 4 in thecentre. The handle optionally further has a cylindrical protrusion 7 atthe opposite side of the handle 2 to the wedge body 1 to assist inremoving the wedge. An optional cylindrical protrusion 3 on the ridge 10between the handle 2 and the body section 1 may assist in removing thewedge.

In the embodiment of the wedge illustrated in FIGS. 1 to 6 a midsection/portion 9 of the body section 1 the bottom 14 of the side walls16 are parallel for a least a portion of the wedge body 1 length. Theheight/depth of the wedge between the ridge 10 and the bottom 14 of theside walls is substantially the same height along the body section 1. Inparticular the mid section/portion 9 between the ridge 10 and the bottom14 of the side walls is substantially the same height.

The wedge may be made in various versions from soft to hard. Thematerials to be used may include Santoprene™ thermoplastic vulcanizatesfrom Advanced Elastomer Systems for a soft wedge, polypropylene for ahard wedge and polyethylene for a mid version.

In an alternate embodiment seen in FIGS. 7 to 10 the wedge body 1 has anarrow mid section/portion 9. The narrow mid-portion/mid-section 9 isdesigned to replicate the inter-proximal space more accurately. Thewedge with a narrow mid section/portion 9 when viewed in a plan viewlooks like a wave. The contour of the wedge transitions smoothly betweenthe different width sections.

Further embodiments of the wave wedge can be seen in FIGS. 13 to 27.Different thickness of the wedge and the wedge mid portions aredesirable so that the appropriate wedge can be used depending on theinter-proximal space between teeth.

Referring to FIGS. 13 to 17 a medium sized wedge is illustrated. Thewedge body 1 has three distinct widths, the mid-portion, between themid-portion 9 and the tapered end 8 of the body and between themid-portion 9 and the handle end 11 of the body 1. The second or thirdwidth is the widest point of the wedge. In general the second and thirdcross sections will be the same width but they may be of differentwidth.

The mid portion 9 is the narrowest portion of the body 1. A crosssection through the line C-C is illustrated in FIG. 16. The width 42 ofthe wedge body 1 from the edges 14 of the sides 16 is between 1.0 mm and1.60 mm. The height 43 of the wedge between the ridge and the edge 14 ofthe sides 16 is between 1.6 mm and 2.4 mm.

The second width is between the mid-portion 9 and the tip end 8 of thebody. A cross section through the line D-D is illustrated in FIG. 17.The width 45 of the wedge body 1 from the edges 14 of the sides 16 isbetween 1.6 mm and 2.4 mm. The height 44 of the wedge between the ridgeand the edge 14 of the sides 16 is between 1.6 mm and 2.4 mm.

The third width is between the mid-portion 9 and the handle end 11 ofthe body. A cross section through the line B-B is illustrated in FIG.15. The width 41 of the wedge body 1 from the edges 14 of the sides 16is between 1.6 mm and 2.4 mm. The height 40 of the wedge between theridge and the edge 14 of the sides 16 is between 1.6 mm and 2.4 mm.

Referring to FIGS. 18 to 22 a large size wedge is illustrated. The midportion 9 is the narrowest portion of the body. A cross section throughthe line C-C is illustrated in FIG. 21 and the width 42 of the wedgebody 1 from the edges 14 of the sides 16 is between 1.6 mm and 2.4 mm.The height 43 of the wedge between the ridge and the edge 14 of thesides 16 is between 1.6 mm and 2.4 mm.

The second width is between the mid-portion 9 and the tip end 8 of thebody. A cross section through the line D-D is illustrated in FIG. 22.The width 45 of the wedge body 1 from the edges 14 of the sides 16 isbetween 2.4 trim and 3.6 mm. The height 44 of the wedge between theridge and the edge 14 of the sides 16 is between 1.6 mm and 2.4 mm.

The third width is between the mid-portion 9 and the handle end 11 ofthe body. A cross section through the line B-B is illustrated in FIG.20. The width 41 of the wedge body 1 from the edges 14 of the sides 16is between mm and mm. The height 40 of the wedge between the ridge andthe edge 14 of the sides 16 is between 1.6 mm and 2.4 mm.

Referring to FIGS. 23 to 17 a small size wedge is illustrated. The midportion 9 is the narrowest portion of the body. A cross section throughthe line C-C is illustrated in FIG. 26 and the width 42 of the wedgebody 1 from the edges 14 of the sides 16 is between 0.8 mm and 1.2 mm.The height 43 of the wedge between the ridge and the edge 14 of thesides 16 is between 1.2 mm and 1.8 mm.

The second width is between the mid-portion 9 and the tip end 8 of thebody. A cross section through the line D-D is illustrated in FIG. 27.The width 45 of the wedge body 1 from the edges 14 of the sides 16 isbetween 1.3 mm and 2.0 mm. The height 44 of the wedge between the ridgeand the edge 14 of the sides 16 is between 1.2 mm and 1.8 mm.

The third width is between the mid-portion 9 and the handle end 11 ofthe body. A cross section through the line B-B is illustrated in FIG.25. The width 41 of the wedge body 1 from the edges 14 of the sides 16is between 1.3 mm and 2.0 mm. The height 40 of the wedge between theridge and the edge 14 of the sides 16 is between 1.2 mm and 1.8 mm.

Referring to FIGS. 11 and 12 the wedge is used in the following manner.A dentist positions their preferred type of matrix band 30 or sectionalmatrix on the tooth 20 in the usual manner. The handle 2 of the wedge isheld with a pair of pin-tweezers not illustrated (described in NewZealand Patent 537463) or conventional tweezers. The wedge is thenplaced between the matrix band 30 and the neighbouring tooth 20 in aconventional manner. After the restorative material has been placed, thewedge is removed by either grasping the hole 4 with the pin-tweezers orgripping the wedge body 1 close to the projection 3 using conventionaltweezers. This projection 3 helps prevent the tweezers from slippingwhen the wedge is being removed.

The wedge is advantageous over the prior art in that the mid-section 9of the wedge is flexible, which allowing the wedge to seal the gingivalmargin of the matrix band at both the buccal and lingual side. Thehandle 2 with a hole 4 provides an excellent means to hold the wedge,particularly with pin-tweezers.

The curvature of the wedge body 1 enables the dentist to insert thewedge into the inter-proximal space without it piercing the gingivalpapilla on the other side. The use of a V-shaped cross-section increasesthe wedge flexibility and provides a space for the gingival tissues.

The invention claimed is:
 1. A dental wedge, for use in theinter-proximal space between adjacent teeth, said dental wedgecomprising: a tapering section ending at a tip; a body section adjacentto and extending from said tapering section; said body section having across-section formed by a first and a second flexible spaced sidewall,each of said first and second sidewall having a bottom edge, and each ofsaid first and second sidewall converging towards one another away fromthe bottom edge and defining an open-sided hollow space therebetween,wherein flexing of said first and second sidewall of the body sectionallows the wedge to adapt to various contours of the inter-proximalspace and allows gingival tissues to extend into said hollow space, andsaid body section including a first widened section adjacent thetapering section, a narrowing mid-portion adjacent the first widenedsection, and a second widened section adjacent the narrowingmid-portion, wherein the bottom edge of said first and second sidewallfollow a wave-like path through the first widened section, the narrowingmid-portion, and the second widened section, wherein each of the bottomedges defines a profile having a generally concave shape at thenarrowing mid-portion.
 2. The dental wedge of claim 1, wherein each ofthe bottom edges defines a convex shape at the first widened section andthe second widened section.
 3. The dental wedge of claim 1, wherein thecross-section formed by the first and the second flexible spacedsidewall is an inverted V-shaped cross-section.
 4. The dental wedge ofclaim 1, further comprising a ridge, wherein the first and secondsidewall converge at the ridge.
 5. The dental wedge of claim 1, whereinthe body section, as viewed from a side is of substantially uniformdepth.
 6. The dental wedge of claim 1, wherein said wedge includes ahandle and said body section extends between said tapering section andsaid handle.
 7. The dental wedge of claim 6, wherein said handleincludes a flat member with a hole there through.
 8. The dental wedge ofclaim 7, wherein a contour of said body section transitions smoothlyalong a length of the body section.
 9. The dental wedge of claim 1,wherein the V-shaped cross-section is continuous along a length of saidbody section and said tapering section.
 10. The dental wedge of claim 9,wherein said tip is blunt, with a leading end radius greater than 0.2mm, and being at least 1.3 mm wide 3 mm from said tip.
 11. The dentalwedge of claim 1, wherein said side walls flex elastically toward eachother during insertion through a space narrower than a widest width ofsaid body section.
 12. The dental wedge of claim 1, wherein a length ofsaid body section is between 10 mm and 20 mm.
 13. The dental wedge ofclaim 1, wherein a maximum width of said body section is between 0.8 mmand 3.6 mm.
 14. The dental wedge of claim 1, wherein a height of thecross-section of said body section is between 1.2 mm and 2.4 mm.
 15. Thedental wedge of claim 1, wherein said V-shaped cross-section includes anangle of between 50° and 25° at a most open cross-section.
 16. Thedental wedge of claim 15, wherein said V-shaped cross-section at saidnarrowing mid-portion includes an angle of between 35° and 15°.
 17. Thedental wedge of claim 1, wherein said V-shaped cross-section at saidnarrowing mid-portion includes an angle of between 35° and 15°.
 18. Thedental wedge of claim 1, wherein the hollow space is a variable size,adapting in size to the flexing of the sidewalls.
 19. The dental wedgeof claim 1, wherein the dental wedge is formed from a single material.20. The dental wedge of claim 1, wherein the flexible sidewalls aresubstantially planar.
 21. The dental wedge of claim 1, wherein the firstand second sidewall bottom edges of the first and second widenedsections, and the narrowing mid-portion transition smoothly between thesections.
 22. The dental wedge of claim 1, wherein the width of theopen-sided hollow space between said first and second sidewall of thefirst and second widened sections is substantially equal.
 23. The dentalwedge of claim 1, wherein the first and second sidewalls are steeper atsaid mid-portion than at regions toward either end of the dental wedge.24. The dental wedge of claim 1, wherein said body section, viewed froma side, has a curved profile, rising to the taper section and curveddownward toward said mid-portion.
 25. The dental wedge of claim 24,wherein at its lowest point along the wedge, the upper edge of the wedgeis spaced between 0.6 mm and 1.1 mm from a line extending between theupper edge of the wedge adjacent the tip and the upper edge of the wedgeadjacent the handle.